Jul 28, 2017 · 1 min read
A quick glance might appear to support your statement. Closer examination reveals that neither is a good example of what you are trying to demonstrate, which makes this an unhelpful example.
The first example may use an excessive line length for mobile, but even a line length of 30–40 characters would be problematic when ~1/3 of your screen width is taken up by something other than the primary content.
A closer look at the second example will demonstrate that most of the lines in that image are 40–50 characters in length, making the overall range for that particular example ~35–50, which happens to be ~2/3 of the 50–75 range you mentioned as optimal for print.